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1.
Langmuir ; 40(24): 12573-12593, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38843172

RESUMO

Through the substitution reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and sodium lignosulfonate (LS), a novel phosphorus-containing sodium lignosulfonate (DAL) was successfully synthesized via the solvothermal method and used as a multifunctional flame retardant to prepare a novel silicone-acrylic emulsion (SAE) composite Si-P-C coating. The structure of DAL was determined by X-ray diffraction (XRD), attenuated total reflection infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and nuclear magnetic resonance (solid-state 13C NMR and 31P NMR). The results demonstrated that incorporating an appropriate dosage of DAL (0.9 g, 1.5 wt %) into SAE-based composite coatings enhances flame retardancy and reduces heat release and smoke production during burning. The peak heat release rate (p-HRR) decreases from 236.7 to 120.3 kW·m-2, total smoke production (TSP) decreases by 71.1%, and the flame-retardant index increases from 1.00 to 4.58. Meanwhile, the coating is transformed into a dense and nonflammable vitreous polyphosphate barrier layer during the firing process to prevent heat or mass transfer. Furthermore, the pyrolysis kinetics identify that the 3D Z-L-T model governs the coatings' pyrolysis, and the appropriate DAL makes the pyrolysis Eα climb from 300.98 to 331.30 kJ·mol-1 at 358-439 °C. Hence, this study presents a new synthesis method of multifunctional flame retardant DAL, studies the excellent properties and cross-linking mechanism of DAL-doped SAE-composite Si-P-C coatings, and explores a halogen-free, low-carbon, and clean eco-technology strategy.

2.
Crit Care ; 28(1): 250, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026242

RESUMO

BACKGROUND: Although cumulative studies have demonstrated a beneficial effect of high-flow nasal cannula oxygen (HFNC) in acute hypercapnic respiratory failure, randomized trials to compare HFNC with non-invasive ventilation (NIV) as initial treatment in acute exacerbations of chronic obstructive pulmonary disease (AECOPD) patients with acute-moderate hypercapnic respiratory failure are limited. The aim of this randomized, open label, non-inferiority trial was to compare treatment failure rates between HFNC and NIV in such patients. METHODS: Patients diagnosed with AECOPD with a baseline arterial blood gas pH between 7.25 and 7.35 and PaCO2 ≥ 50 mmHg admitted to two intensive care units (ICUs) at a large tertiary academic teaching hospital between March 2018 and December 2022 were randomly assigned to HFNC or NIV. The primary endpoint was the rate of treatment failure, defined as endotracheal intubation or a switch to the other study treatment modality. Secondary endpoints were rates of intubation or treatment change, blood gas values, vital signs at one, 12, and 48 h, 28-day mortality, as well as ICU and hospital lengths of stay. RESULTS: 225 total patients (113 in the HFNC group and 112 in the NIV group) were included in the intention-to-treat analysis. The failure rate of the HFNC group was 25.7%, while the NIV group was 14.3%. The failure rate risk difference between the two groups was 11.38% (95% CI 0.25-21.20, P = 0.033), which was higher than the non-inferiority cut-off of 9%. In the per-protocol analysis, treatment failure occurred in 28 of 110 patients (25.5%) in the HFNC group and 15 of 109 patients (13.8%) in the NIV group (risk difference, 11.69%; 95% CI 0.48-22.60). The intubation rate in the HFNC group was higher than in the NIV group (14.2% vs 5.4%, P = 0.026). The treatment switch rate, ICU and hospital length of stay or 28-day mortality in the HFNC group were not statistically different from the NIV group (all P > 0.05). CONCLUSION: HFNC was not shown to be non-inferior to NIV and resulted in a higher incidence of treatment failure than NIV when used as the initial respiratory support for AECOPD patients with acute-moderate hypercapnic respiratory failure. TRIAL REGISTRATION: chictr.org (ChiCTR1800014553). Registered 21 January 2018, http://www.chictr.org.cn.


Assuntos
Cânula , Hipercapnia , Ventilação não Invasiva , Oxigenoterapia , Doença Pulmonar Obstrutiva Crônica , Insuficiência Respiratória , Humanos , Doença Pulmonar Obstrutiva Crônica/terapia , Doença Pulmonar Obstrutiva Crônica/complicações , Masculino , Ventilação não Invasiva/métodos , Ventilação não Invasiva/estatística & dados numéricos , Feminino , Idoso , Oxigenoterapia/métodos , Oxigenoterapia/estatística & dados numéricos , Oxigenoterapia/normas , Pessoa de Meia-Idade , Insuficiência Respiratória/terapia , Hipercapnia/terapia , Hipercapnia/etiologia , Idoso de 80 Anos ou mais , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/estatística & dados numéricos
3.
J Nanobiotechnology ; 22(1): 382, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951872

RESUMO

Reperfusion therapy is critical for saving heart muscle after myocardial infarction, but the process of restoring blood flow can itself exacerbate injury to the myocardium. This phenomenon is known as myocardial ischemia-reperfusion injury (MIRI), which includes oxidative stress, inflammation, and further cell death. microRNA-146a (miR-146a) is known to play a significant role in regulating the immune response and inflammation, and has been studied for its potential impact on the improvement of heart function after myocardial injury. However, the delivery of miR-146a to the heart in a specific and efficient manner remains a challenge as extracellular RNAs are unstable and rapidly degraded. Milk exosomes (MEs) have been proposed as ideal delivery platform for miRNA-based therapy as they can protect miRNAs from RNase degradation. In this study, the effects of miR-146a containing MEs (MEs-miR-146a) on improvement of cardiac function were examined in a rat model of MIRI. To enhance the targeting delivery of MEs-miR-146a to the site of myocardial injury, the ischemic myocardium-targeted peptide IMTP was modified onto the surfaces, and whether the modified MEs-miR-146a could exert a better therapeutic role was examined by echocardiography, myocardial injury indicators and the levels of inflammatory factors. Furthermore, the expressions of miR-146a mediated NF-κB signaling pathway-related proteins were detected by western blotting and qRT-PCR to further elucidate its mechanisms. MiR-146 mimics were successfully loaded into the MEs by electroporation at a square wave 1000 V voltage and 0.1 ms pulse duration. MEs-miR-146a can be up-taken by cardiomyocytes and protected the cells from oxygen glucose deprivation/reperfusion induced damage in vitro. Oral administration of MEs-miR-146a decreased myocardial tissue apoptosis and the expression of inflammatory factors and improved cardiac function after MIRI. The miR-146a level in myocardium tissues was significantly increased after the administration IMTP modified MEs-miR-146a, which was higher than that of the MEs-miR-146a group. In addition, intravenous injection of IMTP modified MEs-miR-146a enhanced the targeting to heart, improved cardiac function, reduced myocardial tissue apoptosis and suppressed inflammation after MIRI, which was more effective than the MEs-miR-146a treatment. Moreover, IMTP modified MEs-miR-146a reduced the protein levels of IRAK1, TRAF6 and p-p65. Therefore, IMTP modified MEs-miR-146a exerted their anti-inflammatory effect by inhibiting the IRAK1/TRAF6/NF-κB signaling pathway. Taken together, our findings suggested miR-146a containing MEs may be a promising strategy for the treatment of MIRI with better outcome after modification with ischemic myocardium-targeted peptide, which was expected to be applied in clinical practice in future.


Assuntos
Exossomos , MicroRNAs , Traumatismo por Reperfusão Miocárdica , NF-kappa B , Ratos Sprague-Dawley , Transdução de Sinais , Animais , MicroRNAs/metabolismo , MicroRNAs/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Exossomos/metabolismo , NF-kappa B/metabolismo , Ratos , Masculino , Leite/química , Miocárdio/metabolismo , Cardiotônicos/farmacologia , Miócitos Cardíacos/metabolismo
4.
J Environ Sci (China) ; 140: 59-68, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38331515

RESUMO

Because of global warming, people have paid more attention to greenhouse gas emitted by vehicles. To quantify the impact of temperature on vehicle CO2 emissions, this study was conducted using the world light vehicle test cycle on two light-duty E10 gasoline vehicles at ambient temperatures of -10, 0, 23, and 40℃, and found that CO2 emission factors of Vehicle 1 in the low-speed phase were 22.07% and 20.22% higher than those of Vehicle 2 at cold start and hot start under -10℃. The reason was vehicle 1 had a larger displacement and more friction pairs than vehicle 2. There was the highest CO2 emission at the low-speed phase due to low average speed, frequent acceleration, and deceleration. The CO2 temperature factor and the ambient temperature had a strong linear correlation (R2 = 0.99). According to CO2 temperature factors and their relationships, CO2 emission factors of other ambient temperatures could be calculated when the CO2 emission factor of 23℃ was obtained, and the method also could be used to obtain the CO2 temperature factors of different vehicles. To separate the effect of load setting and temperature variation on CO2 emission quantitatively, a method was proposed. And results showed that the load setting was dominant for the CO2 emission variation. Compared with 23℃, the CO2 emission for vehicle 1 caused by load setting variation were 62.83 and 47.42 g/km, respectively at -10 and 0℃, while those for vehicle 2 were 45.01 and 35.63 g/km, respectively.


Assuntos
Poluentes Atmosféricos , Humanos , Poluentes Atmosféricos/análise , Temperatura , Dióxido de Carbono/análise , Emissões de Veículos/análise , Gasolina/análise , Veículos Automotores
5.
Stroke ; 54(8): 2114-2125, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37377010

RESUMO

BACKGROUND: The ubiquitin-proteasome system (UPS) and autophagy are 2 major protein degradation pathways in eukaryotic cells. We previously identified a switch from UPS to autophagy with changes in BAG3 (B-cell lymphoma 2-associated-athanogene 3) expression after cerebral ischemia in mice. BAG3 is an antiapoptotic-cochaperone that is directly involved in cellular protein quality control as a mediator for selective macroautophagy. Here, we aimed to investigate the role of BAG3 in ischemic stroke. METHODS: Middle cerebral artery occlusion/reperfusion (MCAO/R) and oxygen-glucose deprivation/reoxygenation were used to mimic cerebral ischemia in vivo and in vitro. The UPS inhibitor MG132 and autophagy inhibitor 3-MA (3-methyladenine) were administered to mice to identify how BAG3 was involved after MCAO/R. Adeno-associated virus and lentiviral vector were used to regulate BAG3 expression in vivo and in vitro, respectively. Behavioral tests, 2,3,5-triphenyltetrazolium chloride staining, and Hematoxylin & Eosin staining were performed to evaluate cerebral injury following MCAO/R, and a Cell Counting kit-8 assay was conducted to assess oxygen-glucose deprivation/reoxygenation-induced injury in cells. Brain tissues and cell lysates were collected and analyzed for UPS activation, autophagy, and apoptosis. RESULTS: The UPS inhibitor alleviated MCAO injury in mice and increased autophagy and BAG3 expression, whereas the autophagy inhibitor exacerbated MCAO/R-induced injury. In addition, BAG3 overexpression significantly improved neurological outcomes, reduced infarct volume in vivo, and enhanced cell survival by activating autophagy and suppressing apoptosis in vitro. CONCLUSIONS: Our findings indicate that BAG3 overexpression activates autophagy and inhibits apoptosis to prevent cerebral ischemia/reperfusion and hypoxia/reoxygenation injury, suggesting a potential therapeutic benefit of BAG3 expression in cerebral ischemia.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Traumatismo por Reperfusão , Animais , Camundongos , Apoptose , Autofagia , Isquemia Encefálica/metabolismo , Glucose , Infarto da Artéria Cerebral Média , Oxigênio , Traumatismo por Reperfusão/metabolismo
6.
J Neuroinflammation ; 20(1): 210, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37715288

RESUMO

BACKGROUND: The intravenous delivery of adult neural precursor cells (NPC) has shown promising results in enabling cerebroprotection, brain tissue remodeling, and neurological recovery in young, healthy stroke mice. However, the translation of cell-based therapies to clinical settings has encountered challenges. It remained unclear if adult NPCs could induce brain tissue remodeling and recovery in mice with hyperlipidemia, a prevalent vascular risk factor in stroke patients. METHODS: Male mice on a normal (regular) diet or on cholesterol-rich Western diet were exposed to 30 min intraluminal middle cerebral artery occlusion (MCAO). Vehicle or 106 NPCs were intravenously administered immediately after reperfusion, at 3 day and 7 day post-MCAO. Neurological recovery was evaluated using the Clark score, Rotarod and tight rope tests over up to 56 days. Histochemistry and light sheet microscopy were used to examine ischemic injury and brain tissue remodeling. Immunological responses in peripheral blood and brain were analyzed through flow cytometry. RESULTS: NPC administration reduced infarct volume, blood-brain barrier permeability and the brain infiltration of neutrophils, monocytes, T cells and NK cells in the acute stroke phase in both normolipidemic and hyperlipidemic mice, but increased brain hemorrhage formation and neutrophil, monocyte and CD4+ and CD8+ T cell counts and activation in the blood of hyperlipidemic mice. While neurological deficits in hyperlipidemic mice were reduced by NPCs at 3 day post-MCAO, NPCs did not improve neurological deficits at later timepoints. Besides, NPCs did not influence microglia/macrophage abundance and activation (assessed by morphology analysis), astroglial scar formation, microvascular length or branching point density (evaluated using light sheet microscopy), long-term neuronal survival or brain atrophy in hyperlipidemic mice. CONCLUSIONS: Intravenously administered NPCs did not have persistent effects on post-ischemic neurological recovery and brain remodeling in hyperlipidemic mice. These findings highlight the necessity of rigorous investigations in vascular risk factor models to fully assess the long-term restorative effects of cell-based therapies. Without comprehensive studies in such models, the clinical potential of cell-based therapies cannot be definitely determined.


Assuntos
Células-Tronco Neurais , Acidente Vascular Cerebral , Masculino , Animais , Camundongos , Neurônios , Hemorragias Intracranianas , Encéfalo
7.
Microvasc Res ; 145: 104442, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36206847

RESUMO

The lymphatic vascular system is crucial for the regulation of tissue fluid homeostasis, lipid metabolism, and immune function. Cardiac injury quickly leads to myocardial edema, cardiac lymphatic dysfunction, which ultimately results in myocardial fluid imbalance and cardiac dysfunction. Therefore, lymphangiogenesis-targeted therapy may improve the recovery of myocardial function post cardiac ischemia as observed in myocardial infarction (MI). Indeed, a promising strategy for the clinical treatment of MI relies on vascular endothelial growth factor-C (VEGF-C)-targeted therapy, which promotes lymphangiogenesis. However, much effort is needed to identify the mechanisms of lymphatic transport in response to heart disease. This article reviews regulatory factors of lymphangiogenesis, and discusses the effects of lymphangiogenesis on cardiac function after cardiac injury and its regulatory mechanisms. The involvement of stem cells on lymphangiogenesis was also discussed as stem cells could differentiate into lymphatic endothelial cells (LECs) and stimulate phenotype of LECs.


Assuntos
Vasos Linfáticos , Infarto do Miocárdio , Isquemia Miocárdica , Humanos , Células Endoteliais/metabolismo , Linfangiogênese , Vasos Linfáticos/metabolismo , Infarto do Miocárdio/metabolismo , Isquemia Miocárdica/metabolismo , Miocárdio/metabolismo , Fator C de Crescimento do Endotélio Vascular/metabolismo
8.
Mol Pharm ; 20(2): 886-904, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36563052

RESUMO

The integration of progressive technologies such as nanomedicine with the use of natural products from traditional medicine (TM) provides a unique opportunity for the longed-for harmonization between traditional and modern medicine. Although several actions have been initiated decades ago, a disparity of reasons including some misunderstandings between each other limits the possibilities of a truly complementation. Herein, we analyze some common challenges between nanomedicine and traditional Chinese medicine (TCM). These challenges, if solved in a consensual way, can give a boost to such harmonization. Nanomedicine is a recently born technology, while TCM has been used by the Chinese people for thousands of years. However, for these disciplines, the regulation and standardization of many of the protocols, especially related to the toxicity and safety, regulatory aspects, and manufacturing procedures, are under discussion. Besides, both TCM and nanomedicine still need to achieve a wider social acceptance. Herein, we first briefly discuss the strengths and weaknesses of TCM. This analysis serves to focus afterward on the aspects where TCM and nanomedicine can mutually help to bridge the existing gaps between TCM and Western modern medicine. As discussed, many of these challenges can be applied to TM in general. Finally, recent successful cases in scientific literature that merge TCM and nanomedicine are reviewed as examples of the benefits of this harmonization.


Assuntos
Produtos Biológicos , Medicamentos de Ervas Chinesas , Humanos , Medicina Tradicional Chinesa , Medicamentos de Ervas Chinesas/uso terapêutico , Nanomedicina
9.
Analyst ; 148(16): 3870-3875, 2023 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-37439439

RESUMO

Angiogenesis is one of the most essential developmental processes and plays a key role in organogenesis and tumorigenesis in which epithelial cells proliferate and migrate, thus resulting in sprouting and extension of the existing vasculature. The study of angiogenesis in vivo is limited by difficulties related to imaging of the fine structure of vascular sprouting within non-transparent bulk tissue. Thus, many model systems have been proposed in recent years. However, to meet the urgent need for high-throughput studies and screening, further improvements are still required, particularly in terms of scaling-up. In this study, we combined microchip fabrication with the culture of three-dimensional (3D) spheroids, thus providing a platform for 3D multilayer angiogenesis-on-a-chip. Using this platform, we investigated the precise effects of vascular endothelial growth factor (VEGF) on angiogenesis. In comparison with two-dimensional (2D) angiogenesis assays, our 3D angiogenesis platform demonstrated superior sprouting and provided proof of concept that our 3D biomimetic angiogenesis-on-a-chip could serve as a powerful tool for pro- or anti-angiogenesis candidate drug screening.


Assuntos
Esferoides Celulares , Fator A de Crescimento do Endotélio Vascular , Biomimética , Células Epiteliais
10.
Environ Res ; 232: 116396, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37327837

RESUMO

NOx emissions from diesel vehicles generally deteriorate with increased durability mileage owing to the wear and deterioration of engines and after-treatment systems. Three China-VI heavy-duty diesel vehicles (HDDVs) were selected for four-phase long-term real driving emission (RDE) tests using the portable emission measurement system (PEMS). After 200,000 km of on-road driving, the maximum NOx emission factor of the test vehicles (387.06 mg/kWh) was found to be significantly lower than the NOx limit of 690 mg/kWh. Under all driving conditions, the NOx conversion efficiency of selected catalytic reduction (SCR) decreased almost linearly as the durability mileage increased. Importantly, the deterioration rate of the NOx conversion efficiency in low-temperature intervals was discernibly higher than that in high-temperature intervals. The NOx conversion efficiency at 200 °C dropped by 16.67-19.82% with higher durability mileage; however, the highest values at 275-400 °C only decreased by 4.11%. Interestingly, the SCR catalyst at 250 °C showed strong NOx conversion efficiency and durability (maximum decline of 2.11%). Overall, the poor de-NOx performance of SCR catalysts at low temperatures significantly challenges the long-term effective control of NOx emissions from HDDVs. Thus, improving the NOx conversion efficiency and durability at low-temperature intervals is the top priority for SCR catalyst optimization; NOx emissions from HDDVs at low velocities and loads should also be monitored by environmental authorities. The linear fitting coefficient for the NOx emission factors of the four-phase RDE tests was 0.90-0.92, indicating that NOx emissions deteriorated linearly with an increase in mileage. Based on the linear fitting results, the NOx emission control of the test vehicles during 700,000 km of on-road driving was highly likely to be qualified. These results can be used by environmental authorities to supervise the NOx emission conformity of in-use HDDVs after validation using other types of vehicles.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Emissões de Veículos/análise , Veículos Automotores , China , Catálise , Gasolina
11.
Int J Mol Sci ; 24(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-38003320

RESUMO

Hypericum perforatum (St. John's Wort) is a medicinal plant from the Hypericaceae family. Here, we sequenced the whole chloroplast genome of H. perforatum and compared the genome variation among five Hypericum species to discover dynamic changes and elucidate the mechanisms that lead to genome rearrangements in the Hypericum chloroplast genomes. The H. perforatum chloroplast genome is 139,725 bp, exhibiting a circular quadripartite structure with two copies of inverted repeats (IRs) separating a large single-copy region and a small single-copy region. The H. perforatum chloroplast genome encodes 106 unique genes, including 73 protein-coding genes, 29 tRNAs, and 4 rRNAs. Hypericum chloroplast genomes exhibit genome rearrangement and significant variations among species. The genome size variation among the five Hypericum species was remarkably associated with the expansion or contraction of IR regions and gene losses. Three genes-trnK-UUU, infA, and rps16-were lost, and three genes-rps7, rpl23, and rpl32-were pseudogenized in Hypericum. All the Hypericum chloroplast genomes lost the two introns in clpP, the intron in rps12, and the second intron in ycf3. Hypericum chloroplast genomes contain many long repeat sequences, suggesting a role in facilitating rearrangements. Most genes, according to molecular evolution assessments, are under purifying selection.


Assuntos
Clusiaceae , Genoma de Cloroplastos , Hypericum , Hypericum/genética , Clusiaceae/genética , Sequência de Bases , Sequências Repetitivas de Ácido Nucleico , Filogenia , Evolução Molecular
12.
Sensors (Basel) ; 22(7)2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35408210

RESUMO

Circular synthetic aperture radar (CSAR), which can observe the region of interest for a long time and from multiple angles, offers the opportunity for moving-target detection (MTD). However, traditional MTD methods cannot effectively solve the problem of high probability of false alarm (PFA) caused by strong clutter. To mitigate this, a novel, three-step scheme combining clutter background extraction, multichannel clutter suppression, and the degree of linear consistency of radial velocity interferometric phase (DLRVP) test is proposed. In the first step, the spatial similarity of the scatterers and the correlation between sub-aperture images are fused to extract the strong clutter mask prior to clutter suppression. In the second step, using the data remaining after elimination of the background clutter in Step 1, an amplitude-based detector with higher processing gain is utilized to detect potential moving targets. In the third step, a novel test model based on DLRVP is proposed to further reduce the PFA caused by isolated strong scatterers. After the above processing, almost all false alarms are excluded. Measured data verified that the PFA of the proposed method is only 20% that of the comparison method, with improved detection of slow and weakly moving targets and with better robustness.

13.
J Environ Manage ; 319: 115737, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35982557

RESUMO

The light-duty moving average window (MAW) method, used for China 6 real driving emission (RDE) calculation, is quite complex with various boundaries. Previous research noticed that the MAW might underestimate the calculation results, while the reasons for this underestimation haven't been studied systematically. With 29 vehicles tested in 10 cities and different boundaries applied for calculation, this study quantitively analyzed the problem, causes, and impacts of the light-duty MAW method. The instantaneous utilization factor (IUF) is proposed for reason analysis. The current MAW method could weaken the supervision of real driving tests as more than 75% of the tests underestimated MAW results, with the largest underestimation being around 100%. The data exclusion could lead to biased MAW results. But without the exclusion, the MAW result couldn't always get an increase due to the IUF and window weighting factor variation. With the extended factors removed, the MAW result bias is significantly reduced. The MAW will lead to a lower IUF of the data at the start/end of the tests, and when the cold-start data is considered, this low utilization must be noticed. The effect from the data exclusion, extended factors, and the window characteristics are closely coupled and they should be taken into consideration simultaneously to consummate the calculation method. The current drift-check progress couldn't effectively monitor the portable emission measurement system (PEMS), especially during the tests. The MAW result might lead to unreasonable emission limits and the emission inventory. Relevant policy based on these results might be implausible.


Assuntos
Poluentes Atmosféricos , Emissões de Veículos , Poluentes Atmosféricos/análise , China , Cidades , Veículos Automotores , Emissões de Veículos/análise
14.
Pharm Biol ; 60(1): 1721-1731, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36086864

RESUMO

CONTEXT: Taohong Siwu decoction (THSWD) has been shown to promote heart repair in myocardial infarction. OBJECTIVE: To determine the effects of modified THSWD (THSWD plus four ingredients) on myocardial ischaemia and reperfusion (I/R) injury. MATERIALS AND METHODS: Sixty Sprague-Dawley rats were randomly divided into the I/R group and three different modified THSWD dose groups (gavage administration, 1.215, 2.43, and 4.86 g, respectively). 2,3,5-Triphenyltetrazolium chloride and Evans blue staining were used to detect the infarct area at 24 h after treatment. The serum biochemical indexes and cell apoptosis were examined to determine myocardial injury. The number of endogenous stem cells, expression of stromal dell derived factor-1 (SDF-1) and stem cell factor (SCF), and cardiac function were measured at 4 weeks. The serum was collected for metabolomic analysis. RESULTS: The high-dose modified THSWD group presented a reduced infarction area (decreased by 21.3%), decreased levels of lactate dehydrogenase and creatinine kinase, attenuated cell apoptosis, and enhanced superoxide dismutase activity in early stage I/R compared with other groups. The serum SCF and SDF-1 levels were higher in the high-dose group than in the I/R group. At 4 weeks, the infarct size and collagen content were the lowest, and the ejection fraction and fractional shortening values were the highest in the high-dose group. Moreover, high-dose modified THSWD affected the metabolism of phosphonate and phosphonate, taurine, and hypotaurine. CONCLUSIONS: Endogenous stem cell mobilization and metabolic regulation were related to the cardioprotection of modified THSWD. We provided a new strategy and direction for the treatment of cardiovascular diseases with traditional Chinese medicine.


Assuntos
Infarto do Miocárdio , Traumatismo por Reperfusão Miocárdica , Organofosfonatos , Animais , Medicamentos de Ervas Chinesas , Mobilização de Células-Tronco Hematopoéticas , Infarto do Miocárdio/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Organofosfonatos/uso terapêutico , Ratos , Ratos Sprague-Dawley , Reperfusão
15.
Plant Physiol ; 184(2): 1024-1041, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32663166

RESUMO

Spatiotemporally regulated callose deposition is an essential, genetically programmed phenomenon that promotes pollen development and functionality. Severe male infertility is associated with deficient callose biosynthesis, highlighting the significance of intact callose deposition in male gametogenesis. The molecular mechanism that regulates the crucial role of callose in production of functional male gametophytes remains completely unexplored. Here, we provide evidence that the gradual upregulation of a previously uncharacterized cotton (Gossypium hirsutum) pollen-specific SKS-like protein (PSP231), specifically at the post pollen-mitosis stage, activates callose biosynthesis to promote pollen maturation. Aberrant PSP231 expression levels caused by either silencing or overexpression resulted in late pollen developmental abnormalities and male infertility phenotypes in a dose-dependent manner, highlighting the importance of fine-tuned PSP231 expression. Mechanistic analyses revealed that PSP231 plays a central role in triggering and fine-tuning the callose synthesis and deposition required for pollen development. Specifically, PSP231 protein sequesters the cellular pool of RNA-binding protein GhRBPL1 to destabilize GhWRKY15 mRNAs, turning off GhWRKY15-mediated transcriptional repression of GhCalS4/GhCalS8 and thus activating callose biosynthesis in pollen. This study showed that PSP231 is a key molecular switch that activates the molecular circuit controlling callose deposition toward pollen maturation and functionality and thereby safeguards agricultural crops against male infertility.


Assuntos
Gametogênese/genética , Gametogênese/fisiologia , Glucanos/biossíntese , Gossypium/fisiologia , Proteínas de Plantas/genética , Pólen/crescimento & desenvolvimento , Pólen/genética , Produtos Agrícolas/citologia , Produtos Agrícolas/genética , Produtos Agrícolas/fisiologia , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Glucanos/genética , Gossypium/citologia , Gossypium/genética , Proteínas de Plantas/metabolismo , Pólen/citologia , Pólen/metabolismo
16.
Ecotoxicol Environ Saf ; 222: 112520, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34280842

RESUMO

Mineral development and metal smelting are the main sources of heavy metal pollution, and copper (Cu) and cadmium (Cd) are the most serious mineral elements in heavy metal pollution. Food chain is the main channel for Cu and Cd to enter human body. Excessive accumulation of Cu and Cd can lead to a variety of diseases and threaten human health. Therefore, it is urgent to repair Cu and Cd-contaminated soil. Previous several studies found that sulfur (S) and molybdenum (Mo) had the effect of alleviating the decrease of antioxidant capacity caused by heavy metal poisoning. To investigate the co-combinations of S and Mo fertilizations on antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-contaminated meadow, and explore the control methods of co-pollutions of Cu and Cd in natural pastures, fertilizing and grazing experiments were carried out in the Wumeng Prairie in the northwest of Guizhou Province, Southwest China. 24 hm2 Cu and Cd-polluted meadows were fenced, and were randomly divided into four groups with 3 replications per group and 2 hm2 per replication. The tested groups included the control group (no fertilizer) and the three treatment groups, applied 40 kg S + 1 kg Mo, 80 kg S + 2 kg Mo, and 120 kg S + 3 kg Mo per hectare for group I, group II, and group III, respectively. 72 healthy Guizhou semi-fine wool sheep (one year old, 33.9 ± 1.2 kg) were randomly assigned to the tested pastures with 18 sheep per group. The grazing experiment lasted for 60 days. The results showed that the contents of Mn, Zn, Mo, and S in herbage in fertilized pastures were higher than that in the control group (P < 0.05). The content of Cu in herbage in fertilized pastures was lower than that in the control group (P < 0.05). The contents of Mn, Zn, Mo, and S in serum of grazing Guizhou semi-fine wool sheep were higher than that in the control group (P < 0.05). The content of Cu in serum of grazing Guizhou semi-fine wool sheep was lower than that in the control group (P < 0.05). The levels of blood Hb, RBC, and PCV, and the activities of serum SOD, GSH-Px, T-AOC, CAT, and Cp in group Ⅲ were higher than that in the control group, group Ⅰ, and group Ⅱ (P < 0.05). The MDA content of sheep in group Ⅲ was lower than that in the other treatment sheep (P < 0.05). In summary, the combinations of S and Mo fertilizers influenced the mineral contents in herbage and serum of grazing Guizhou semi-fine wool sheep. The combinations of 120 kg S + 3 kg Mo fertilizer reduced the toxicity and improved antioxidant capacity of grazing Guizhou semi-fine wool sheep in Cu and Cd-polluted grasslands.


Assuntos
Cádmio , , Animais , Antioxidantes , Cádmio/toxicidade , Cobre/toxicidade , Fertilização , Humanos , Molibdênio/toxicidade , Ovinos , Enxofre
17.
Sensors (Basel) ; 21(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670623

RESUMO

Human activity detection plays an important role in social security monitoring. Since human activity is very weak, it is necessary to employ the repeat-pass Interferometric Synthetic Aperture Radar (InSAR) technique to detect the potential activity between two data acquisitions; a high level of coherence is required for detection. With the object of detecting human activity of interest, this paper presents a coherence improvement approach based on sub-aperture InSAR for human activity detection. Different sub-apertures contain different scattering information of the target, as they represent the backscatter of the target from a different range of angles. Integrating corresponding sub-aperture interferometric results can improve the coherence between two complex images compared to the entire synthetic aperture, as well as removing a little disturbance in some circumstances. To validate the method presented in this paper, the actual airborne Ka-band frequency modulated continuous wave (FMCW) InSAR data acquired by the Aerospace Information Research Institute, Chinese Academy of Sciences (AIRCAS) are utilized. The experimental results demonstrate that the proposed method can effectively improve the coherence between two complex SAR images and can validly detect human activity of interest.


Assuntos
Atividades Humanas , Interferometria , Radar , Humanos
18.
Stroke ; 51(5): 1570-1577, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32212900

RESUMO

Background and Purpose- Ischemic stroke impairs endoplasmic reticulum (ER) function, causes ER stress, and activates the unfolded protein response. The unfolded protein response consists of 3 branches controlled by ER stress sensor proteins, which include PERK (protein kinase RNA-like ER kinase). Activated PERK phosphorylates eIF2α (eukaryotic initiation factor 2 alpha), resulting in inhibition of global protein synthesis. Here, we aimed to clarify the role of the PERK unfolded protein response branch in stroke. Methods- Neuron-specific and tamoxifen-inducible PERK conditional knockout (cKO) mice were generated by cross-breeding Camk2a-CreERT2 with Perkf/f mice. Transient middle cerebral artery occlusion was used to induce stroke. Short- and long-term stroke outcomes were evaluated. Protein synthesis in the brain was assessed using a surface-sensing-of-translation approach. Results- After tamoxifen-induced deletion of Perk in forebrain neurons was confirmed in PERK-cKO mice, PERK-cKO and control mice were subjected to transient middle cerebral artery occlusion and 3 days or 3 weeks recovery. PERK-cKO mice had larger infarcts and worse neurological outcomes compared with control mice, suggesting that PERK-induced eIF2α phosphorylation and subsequent suppression of translation protects neurons from ischemic stress. Indeed, better stroke outcomes were observed in PERK-cKO mice that received postischemic treatment with salubrinal, which can restore the ischemia-induced increase in phosphorylated eIF2α in these mice. Finally, our data showed that post-treatment with salubrinal improved functional recovery after stroke. Conclusions- Here, we presented the first evidence that postischemic suppression of translation induced by PERK activation promotes recovery of neurological function after stroke. This confirms and further extends our previous observations that recovery of ER function impaired by ischemic stress critically contributes to stroke outcome. Therefore, future research should include strategies to improve stroke outcome by targeting unfolded protein response branches to restore protein homeostasis in neurons.


Assuntos
Estresse do Retículo Endoplasmático/genética , Fator de Iniciação 2 em Eucariotos/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Neurônios/metabolismo , Neuroproteção/genética , Resposta a Proteínas não Dobradas/genética , eIF-2 Quinase/genética , Animais , Isquemia Encefálica/metabolismo , Isquemia Encefálica/fisiopatologia , Cinamatos/farmacologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fator de Iniciação 2 em Eucariotos/efeitos dos fármacos , Infarto da Artéria Cerebral Média/fisiopatologia , Camundongos , Camundongos Knockout , Fosforilação , Biossíntese de Proteínas/efeitos dos fármacos , Biossíntese de Proteínas/genética , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Tioureia/análogos & derivados , Tioureia/farmacologia , Resposta a Proteínas não Dobradas/efeitos dos fármacos
19.
Curr Issues Mol Biol ; 35: 127-144, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31422937

RESUMO

Brain ischaemia is a severe form of metabolic stress that activates a cascade of pathological events involving many signalling pathways. Modulation of these pathways is largely mediated by post-translational modifications (PTMs). Indeed, PTMs can rapidly modify pre-existing proteins by attaching chemical or polypeptide moieties to selected amino acid residues, altering their functions, stability, subcellular localizations, or interactions with other proteins. Subsequently, related signalling pathways can be substantially affected. Thus, PTMs are widely deployed by cells as an adaptive strategy at the front line to efficiently cope with internal and external stresses. Many types of PTMs have been identified, including phosphorylation, O-GlcNAcylation, small ubiquitin-like modifier (SUMO) modification (SUMOylation), and ubiquitination. All these PTMs have been studied in brain ischaemia to some extent. In particular, a large body of evidence has demonstrated that both global SUMOylation and ubiquitination are massively activated after brain ischaemia, and this activation may play a critical role in defining the fate and function of cells in the post-ischaemic brain. The goal of this review will be to summarize the current findings on SUMOylation and ubiquitination in brain ischaemia and discuss their clinical implications.


Assuntos
Isquemia Encefálica/enzimologia , Isquemia Encefálica/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Modificadoras Pequenas Relacionadas à Ubiquitina/metabolismo , Sumoilação , Ubiquitinação , Animais , Isquemia Encefálica/patologia , Isquemia Encefálica/terapia , Linhagem Celular , Humanos , Proteoma/genética , Proteoma/metabolismo , Transdução de Sinais/genética
20.
BMC Plant Biol ; 20(1): 217, 2020 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-32410659

RESUMO

BACKGROUND: Mitogen-activated protein kinase kinase kinases (MAPKKKs) are significant components in the MAPK signal pathway and play essential roles in regulating plants against drought stress. To explore MAPKKK gene family functioning in cotton response and resistance to drought stress, we conducted a systematic analysis of GhMAPKKKs. RESULTS: In this study, 157 nonredundant GhMAPKKKs (including 87 RAFs, 46 MEKKs and 24 ZIKs) were identified in cotton (Gossypium hirsutum). These GhMAPKKK genes are unevenly distributed on 26 chromosomes, and segmental duplication is the major way for the enlargement of MAPKKK family. Furthermore, members within the same subfamily share a similar gene structure and motif composition. A lot of cis-elements relevant to plant growth and response to stresses are distributed in promoter regions of GhMAPKKKs. Additionally, these GhMAPKKKs show differential expression patterns in cotton tissues. The transcription levels of most genes were markedly altered in cotton under heat, cold and PEG treatments, while the expressions of some GhMAPKKKs were induced in cotton under drought stress. Among these drought-induced genes, we selected GhRAF4 and GhMEKK12 for further functional characterization by virus-induced gene silencing (VIGS) method. The experimental results indicated that the gene-silenced cotton displayed decreased tolerance to drought stress. Malondialdehyde (MDA) content was higher, but proline accumulation, relative leaf water content and activities of superoxide dismutase (SOD) and peroxidase (POD) were lower in the gene-silenced cotton, compared with those in the controls, under drought stress. CONCLUSION: Collectively, a systematic survey of gene structure, chromosomal location, motif composition and evolutionary relationship of MAPKKKs were performed in upland cotton (Gossypium hirsutum). The following expression and functional study showed that some of them take important parts in cotton drought tolerance. Thus, the data presented here may provide a foundation for further investigating the roles of GhMAPKKKs in cotton response and resistance to drought stress.


Assuntos
Secas , Regulação da Expressão Gênica de Plantas , Gossypium/fisiologia , MAP Quinase Quinase Quinases/genética , Família Multigênica , Proteínas de Plantas/genética , Gossypium/genética , MAP Quinase Quinase Quinases/metabolismo , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
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